Re: Streamer formation on the scope...

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <twftesla-at-qwest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:

> >In view of this, with a high-k DC system, it may begin to matter
> >which way the secondary is wound with respect to the primary.
> 
> Yes!!  The polarity was a big factor in the GMHEICSLR coil!!  That single
> shot coil really needed for the first big cycle to be negative to get the
> longest arc!!  It made a dramatic arc length difference if you reversed the
> polarity.

This is the known rectifying action of corona. I think that without
this streamers would not form. The presence of highly mobile extra
negative charge around the coil, that are pushed back and forth
by the intense electric field around the terminal may be essential.
Note that DC doesn't produce streamers, not even at lightning level
power, because there is no AC field to move the free charges. 
Actually, sometimes lightning produces long unconnected branches
during the spark formation, that become briefly bright when they are 
drained back into the main spark channel by the intense electric
field pulse that occurs when the channel is completed. I can 
see this even with sparks from an electrostatic machine.

Antonio Carlos M. de Queiroz